相关论文: 2-2 and 2-3 Intercombination Transitions in Be-lik…

We present three dimensional time-dependent calculations of ionization of arbitrarily spatially oriented H$_2^+$ by attosecond, intense, high-frequency laser fields. The ionization probability shows a strong dependence on both the…

The hyperfine induced $4f^{14}5s5p~^3\mathrm{P}^o_{0,2}~-~4f^{14}5s^2~^1\mathrm{S}_0$ transition probabilities for highly charged Sm-like ions are calculated in the framework of the multi-configuration Dirac-Hartree-Fock method. Electron…

Partial photoionization cross sections from the ^1S ground and the ^3P metastable states of the Be isoelectronic series to different final states including a number of satellite (ionization plus excitation) channels are studied using the…

Accurate values of electric dipole (E1) amplitudes along with their uncertainties for a number of transitions among low-lying states of Mg$^+$, Ca$^+$, Sr$^+$, and Ba$^+$ are listed by carrying out calculations using a relativistic…

This study investigates the ionization and excitation processes induced by electron impact between two configurations or superconfigurations. Rate coefficients are calculated for transition arrays or super-transition arrays rather than…

Calculations of energy levels, radiative rates and lifetimes are reported for 17 F-like ions with 37 $\le$ Z $\le$ 53. For brevity, results are only presented among the lowest 113 levels of the 2s$^2$2p$^5$, 2s2p$^6$, 2s$^2$2p$^4$3$\ell$,…

Precision laser spectroscopy in the extreme ultraviolet of the 1S-2S two-photon transition in singly-ionized helium is a promising route for tests of fundamental physics. We demonstrate laser excitation of this transition in an atomic beam…

We study the role of Penning ionization on the photoassociation spectra of He(^3S)-He(^3S). The experimental setup is discussed and experimental results for different intensities of the probe laser are shown. For modelling the experimental…

In this paper, we have studied electron correlation and Gaunt interaction effects in ionization potentials (IPs) and hyperfine constants A of 2p$^2P_{1/2}$ and 2p$^2P_{3/2}$ states along with the fine structure splitting (FSS) between them…

Binding energies of the $^3P_0$ and $^3P_2$ levels of the $1s^2\,2s\,2p$ electron configuration in berylliumlike xenon are rigorously evaluated using ab initio QED approach. All relevant one- and many-electron QED contributions are…

The dipion transitions $\Upsilon(2S,3S,4S) \to \Upsilon(1S,2S)\pi\pi$ are systematically studied by considering the mechanisms of the hadronization of soft gluons, exchanging the bottomoniumlike $Z_b$ states, and the bottom-meson loops. The…

We report the direct measurement of isotope shifts of the barium 6s$^2$ $^1$S$_0$ --5d6p $^3$D$^\text{o}_1$ 413-nm electric quadrupole transition, which is utilized for efficient barium ion trapping via photoionization using a single…

We calculated QED corrections to the $E1$ transition amplitudes in Ne-like iron and nickel. For the $2p \to 3d$ transitions the dominant effect came from the many-electron mixing, or electronic correlations. For the $2p \to 3s$ transitions…

We report measurements and theoretical calculations of the fine-structure splittings in all three $1s2s\,^3\!S_1\rightarrow\,1s2p\,^3\!P_{0,1,2}$ transitions in the heliumlike systems of the isotopes $^{12,13,14}$C. The metastable triplet…

The hyperfine induced 2s 2p 3P0 -> 2s2 1S0 transition rate in Be-like sulfur was measured by monitoring the decay of isotopically pure beams of 32-S12+ and 33-S12+ ions in a heavy-ion storage ring. Within the 4% experimental uncertainty the…

We present high-accuracy spectroscopy data of line strengths, transition probabilities and oscillator strengths for the allowed transitions among the $nS_{1/2}$, $nP_{1/2,3/2}$ and $n'D_{3/2,5/2}$ states with $n=5$ to $10$ and $n'=4$ to…

We discuss a parity nonconserving (PNC) asymmetry in the cross section of dielectronic recombination of polarized electrons on multiply charged ions with Z>40. This effect is strongly enhanced for close doubly-excited states of opposite…

The polarizabilities and hyperpolarizabilities of the Be$^+$ ion in the $2^2S$ state and the $2^2P$ state are determined. Calculations are performed using two independent methods: i) variationally determined wave functions using Hylleraas…

We have carried absolute frequency measurements of the $(6s^{2})\,^{1}S_{0}$ $-$ $(6s6p)\,^{3}P_{1}$ transition in $^{171}$Yb (the intercombination line), where the spin-1/2 isotope yields two hyperfine lines. The measurements rely on…

The ground-state hyperfine splitting values of high-Z boronlike ions are calculated. Calculation of the interelectronic-interaction contribution is based on a combination of the 1/Z perturbation theory and the large-scale…